Green Day made headlines during their epic set at the iHeartRadio Music Festival, when Billie Joe went on an on-stage rant that included expletives, guitar smashing, and a brash reminder to the audience that he is 'not f***ing Justin Bieber, you motherf*****s.'

"The next morning, I woke up. I asked [my wife] Adrienne, 'How bad was it?' She said, 'It's bad.' I called my manager. He said, 'You're getting on a plane, going back to Oakland and going into rehab immediately.'"

Armstrong did just that - entering rehab right after the festival in Vegas - causing Green Day to postpone planned tour dates.

Of his years of alcohol and prescription drug abuse, Billie Joe tells Rolling Stone, "I couldn't predict where I was going to end up at the end of the night... I'd wake up in a strange house on a couch. I wouldn't remember how. It was a complete blackout."

The band will play their first gig since September at SXSW in Austin, Texas as part of the ACL Live series. They'll also be screening their two documentaries: Broadway Idiot, which follows Armstrong as Green Day helped turn their American Idiot album into a Broadway musical, and ¡Cuatro!, which covers the making of their trilogy of new albums, ¡Uno!, ¡Dos!, and ¡Tré!Green Day is scheduled to get back on the road starting March 28th with a show in Rosemont, Illinois.